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21.
Boris Pejin Kristina Tešanović Dragica Jakovljević Sonja Kaišarević Filip Šibul Milena Rašeta 《Natural product research》2019,33(5):750-754
The polysaccharide (PSH) extracts from the edible mushroom species Coprinus comatus and Coprinellus truncorum were screened in liquid for their acetylcholinesterase inhibitory (AChE) activity. Both extracts were found to display inhibition of the aforementioned enzyme reaching similar IC50 values of 0.62 ± 0.07 and 0.61 ± 0.03 mg/mL, respectively. According to the means of FTIR spectroscopy, these PSH extracts mostly contained β-glucans. However, the presence of some proteins and polyphenolics as minor ingredients were also detected. Compared with existing literature data for anti-AChE activity of the sugar samples, the findings within this study may be treated as a profound bioactivity. Consequently, this study puts some light on the possible use of the screened macrofungi in the palliative treatment of Alzheimer’s disease. 相似文献
22.
A new procedure for determining nitrogenated bases by forming ion pairs with Fe(SCN)63– is studied. The method consists of extracting the ion pair formed by a nitrogenated base and the inorganic complex Fe(SCN)63– into an organic phase, and measuring the iron in the organic phase by AAS at 248.3 nm. The optimal experimental conditions for determining amylocaine, avacan, bromhexine, diphenhydramine and papaverine are studied. The organic phase used is 1,2-dichloroethane. The standard deviation of the method varies between 10–1 and 10–2. The interferences produced by various substances are studied. 相似文献
23.
A. E. Goncharov A. A. Politov N. A. Pankrushina O. I. Lomovskii 《Chemistry of Natural Compounds》2006,42(3):336-339
Extracts of Aconitum septentrionale Koelle roots obtained using chloroform, isopropanol, and ethanol were purified using chloroform and basic γ-Al2O3. Ballast materials were selectively adsorbed by γ-Al2O3, increasing the mass fraction of lappaconitine in the extract. The ethanol extract was purified most. The degree of lappaconitine
extraction by chloroform was unaffected by the presence of γ-Al2O3. However, the mass fraction in the extract and lappaconitine extraction from Aconitum septentrionale were increased more than twice.
__________
Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 274–276, May–June, 2006. 相似文献
24.
Kuan-Hon Lim 《Tetrahedron letters》2006,47(29):5037-5039
A new pentacyclic indole alkaloid of the pericine-type, valparicine, representing the first member of this sub-group, was obtained from a Malayan Kopsia species and the structure was established by spectroscopic analysis. A partial synthesis of valparicine and apparicine from pericine was carried out via the Potier-Polonovski reaction and the biogenetic implications are discussed. 相似文献
25.
Jernej Wagger David Bevk Anton Meden Jurij Svete Branko Stanovnik 《Helvetica chimica acta》2006,89(2):240-248
A series of racemic dipodazine analogues 9 were prepared in 22–80% yield from (3Z,6RS)‐3‐[(dimethylamino)methylidene]‐6‐methyl‐1‐(phenylmethyl)piperazine‐2,5‐dione ( 7 ) (Scheme 1), which was prepared in four steps from (RS)‐alanine methyl ester hydrochloride. The preparation of nonracemic 7 from (S)‐alanine methyl ester hydrochloride failed, since the introduction of the enamino functionality at position 3 of the precursor 6 was accompanied by almost complete racemization. 相似文献
26.
毛细管电泳法研究提取剂对黄连-黄柏共煎剂中生物碱含量的影响 总被引:4,自引:0,他引:4
用毛细管电泳法,对黄连与黄柏配伍后共煎剂中的主要生物碱进行了分析。以50 mmol/L Na2B4O7(pH=7)-CH3OH(85:15,V/V)为背景电解质,操作电压为14 kV,电迁移进样10 kV×5s,柱上223 nm检测,5种主要生物碱9 min内可在50 cm×75μm毛细管上实现基线分离。以小檗碱、巴马汀的提取量为指标,分析了提取剂对提取效果的影响。以30%的乙醇水溶液为提取剂,可得到最大煎出量。 相似文献
27.
D. M. Turdybekov K. M. Turdybekov E. V. Burdel'naya A. Zh. Turmukhambetov S. M. Adekenov Yu. V. Gatilov 《Chemistry of Natural Compounds》2003,39(1):19-21
The structure of lappacontine hydrobromide hydrate was solved by an x-ray structure analysis. 相似文献
28.
Zanolari B Wolfender JL Guilet D Marston A Queiroz EF Paulo MQ Hostettmann K 《Journal of chromatography. A》2003,1020(1):75-89
The bark of catuaba (Erythroxylum vacciniifolium Martius, Erythroxylaceae), a tree native to the northern part of Brazil, was investigated for its alkaloid content. With the aim of obtaining preliminary structure information on-line, the alkaloid extract was analysed by high-performance liquid chromatography coupled to diode array UV detection, to mass spectrometry and to nuclear magnetic resonance. Interpretation of on-line spectroscopic data obtained from this extract led to structural elucidation of six new alkaloids and partial identification of 18 potentially original alkaloids bearing the same tropane skeleton esterified in positions 3 and 6 by 1-methyl-1H-pyrrol-2-carboxylic acid and/or 4-hydroxy-3,5-dimethoxybenzoic acid. 相似文献
29.
用^3HNMR波谱法分析微波激发催化交换制备的^3H标记颠茄类生物碱 总被引:1,自引:0,他引:1
用~3H NMR波谱法测定了微波激发催化交换制备的四种~3H标记颠茄类生物碱示踪剂的氚标记位置及其相对百分含量。并在用~1H NMK归属原料纯度及标记物分子各基因化学位移时采用了水峰抑制技术(简称WEFT),既能同时消除溶剂氘代甲醇及水峰的影响;又能提高灵敏度(近10倍),从而计算出所得标记产物的化学纯度值与放化纯度值。为快速、准确寻找制备标记生物碱的最佳实验条件和控制标记物质量提供了唯一的物理无损分析方法。 相似文献
30.
E. D. Khairitdinova E. M. Tsyrlina L. V. Spirikhin N. I. Fedorov M. S. Yunusov 《Chemistry of Natural Compounds》2005,41(5):575-577
The known alkaloids deltaline, methyllycaconitine, elasine, and the new norditerpene alkaloid alpinine were isolated from
the aerial part of Delphinium alpinum. The structure of the last was proposed as 1α,6β, 16β-trimethoxy-7-hydroxy-8-ethoxy-14α-propionyloxy-4β-(2″-methyl)succinylanthranoyloxymethyl-N-ethylaconitane
on the basis of PMR, 13C NMR, IR, and mass spectra.
__________
Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 469–471, September–October, 2005. 相似文献